1. Field of the Invention
The invention relates to a backlight module applied in a liquid crystal display (LCD), in particular, to a backlight module capable of improving the hotspot and bright line phenomenon and maintaining good light guiding efficiency.
2. Description of the Prior Art
In recent years, with the continuous progress of display technology, the design of the backlight module of the LCD is also continuously researched and developed. Please refer to FIG. 1. FIG. 1 illustrates a cross-sectional view of a backlight module of a conventional LCD in a prior art. As shown in FIG. 1, the backlight module 1 includes a wedge-shaped light guide plate 10, a light source 12, and a light reflecting plate 14. The main reason that the backlight module 1 using the wedge-shaped light guide plate 10 is to prevent the lights emitted by the upper half of the light source surface 120 of the light source 12 from being emitted out of the light guide plate 10, so that the lights can be smoothly emitted into the light guide plate 10 to enhance the efficiency of the light guide plate 10.
The backlight module 1 using the wedge-shaped light guide plate 10 has the above-mentioned advantages, however, as shown in FIG. 1, after the light R emitted by the light source surface 120 of the light source 12 passes through the light-incident surface 100 of the light guide plate 10 to enter into the light guide plate 10, the light R will be reflected out of the bottom surface 104 by the guiding tilt surface 102 of the light guide plate 10, and then emitted to the light reflecting plate 14 under the bottom surface 104. Then, the light reflecting plate 14 will reflect the light R into the wedge-shaped light guide plate 10, and the light R will be upward emitted out of the wedge-shaped light guide plate 10 from the light emitting surface 106 of the wedge-shaped light guide plate 10. As a result, the hot spot phenomenon and the light leakage phenomenon will occur at locations corresponding to the light source 12 of the conventional LCD, and the image quality displayed by the LCD will be seriously affected.